You will need to install JDK 10 in order to build this package. I tried to specify the JDK 10 for building without setting JDK 10 to default java runtime. I believe you will need to set your java runtime in order to run Bisq however. I recommend running archlinux-java set java-10-openjdk to make Java 10 default on your system if you can. This may effect other java applications on your system. For more information on Java see the wiki page: https://wiki.archlinux.org/index.php/Java

I was also able to run export PATH="/usr/lib/jvm/java-10-openjdk/bin/:$PATH"; bisq-desktop while having Java 8 as my default.

The build fails. It has been 18 days since you posted that the package would be updated. If you aren't going to keep this updated, would you mind just creating a stable flatpak so that anyone can install it on any Linux distro without issue? Either way, I appreciate you and all of the other devs.